Cell lysis refers to the process of decomposing a cell such that the membrane of the cell is disrupted and the intercellular components are exposed. Cell lysis is primarily performed in cell classification and protein purification. Cell lysis is generally carried out as an initial stage to separate DNA or RNA in a DNA or RNA amplification process such as PCR (Polymerase Chain Reaction).
Cell lysis for cell disruption is generally classified into optical, mechanical, acoustic, electrical, and chemical cell lysis.
In optical cell lysis, laser micropulses are radiated to a target cell to form a cavitation bubble such that the cell is disrupted through expansion of the cavitation bubble. As such, the optical cell lysis is carried out by radiating laser micropulses into a particular cell or to an adjacent region thereof, causing deformation of the cell and requiring a separate laser generator.
In acoustic cell lysis, a cell solution or suspension is placed in a chamber within an ultrasound bath, followed by application of ultrasound waves to disrupt a target cell. Cell disruption using ultrasound waves requires a long time and makes it difficult to obtain uniform energy distribution of the ultrasound waves, thereby providing inconsistent results.
In electrical cell lysis, an electric field is applied to a cell to generate a membrane potential for cell disruption. Electrical cell lysis is similar to other methods for cell lysis such as a freezing/thawing method, a heating method, an osmotic pressure shock method, and the like in that impact is applied to the cell wall. However, these methods apply thermal impact to the cell, causing degradation of cell proteins.
In chemical cell lysis, the cell wall is disrupted using an acid, base, detergent, solvent, chemotropic material, and the like. In particular, generally used is detergent-based cell lysis wherein a detergent disrupts a lipid double layer of a cell to discharge intercellular components and dissolves membrane proteins. However, such chemical cell lysis disadvantageously causes degradation of cell proteins, and requires separate reagents for cell lysis and removal of the reagents after the cell lysis, and a long time for cell lysis.
On the contrary, mechanical cell lysis is carried out using a mechanical nano structure to disrupt a cell wall. Recently, new lab-on-a chip (LOC)-based cell lysis devices are developed to improve efficiency in cell lysis while providing convenience in repeated experimentation. Among various LOC-based cell lysis devices in the art, a mechanical lysis chip minimizes protein degradation, which can occur by heating, electrical impact, or cleansing upon cell lysis.
Carlo et al. suggested a mechanical cell lysis apparatus wherein a silicon substrate is subjected to deep reactive ion etching (DRIB) to form nanoscale scallops on a sidewall in order to disrupt a cell membrane (D. D. Carlo, K. Jeong and L. P. Lee, “Reagentless mechanical cell lysis by nanoscale barbs in microchannels for sample preparation”, Lab Chip, 2003, 3, 287-291). However, this apparatus entails high cost due to the silicon DRIE process.
Cell lysates resulting from cell lysis are generally used for protein detection (such as western blotting), immune precipitation, and the like. These processes are performed by detecting a certain protein or an intermolecular reaction. It is desirable that cell lysis provide a sufficient amount of protein products and a high concentration of purified proteins. For this purpose, cell lysis needs to be rapidly performed with respect to a target cell using as much fluid as possible through a short passageway, and enables immediate analysis of cell lysates.